a book of shadows is basicly your journal filled with your magick experiences, spells you write, tools you use, divination, or anything else you want. it has been said that "you must write in your own hand writing to give it meaning" but thats not entirely true. I believe you can type it if you have terrible feeling, and give it meaning if you pour your heart into it. also many say you cant use lose pages, but a binder is also good because you can remove or add whatever needs removed or added.
some possible sections for a book of shadows include:
a tittle cover page
consulting your guide/higher self/ etc
books and reference
and maybe even classes you take
each section can have sub categories. depending on what you do.